Grinding machine



Oct. 9, 1934. c. BOOTH 1,976,114 I GRINDING MACHINE Filed June 1930 2 Sheets-Sheet 1 gmenl o'n CLEMENTBOOTH Oct. 9, 1934. c BOOTH 1,976,114

GRINDING MACHINE Filed June 2 1950 2 Sheets-Sheet 2 14W fj 55 gwuento'o 56 CLEMENT B0 0TH 49 Patented Oct. 9, 1934 UNITED STATES PATENT oFFics GRINDING MACHINE Application June 23, 1930, Serial No. 462,956

7 Claims.

This invention relates to improvements in machine tools and especially to improvements in grinding machines.

One of the principal objects of the present invention is to provide an improved mechanism for effecting a slight reciprocation of a grinding wheel to break up grinding lines on the work being operated upon thereby.

Another object of the invention is the provision of improved means that may be adjusted at the will of the operator to vary the reciprocating stroke of the said grinding wheel without dismantling the reciprocating mechanism or changing any of its necessary parts.

Another object of the invention is the provision of improved, novel means for changing the throw of the fulcrum bar to thereby vary the effective are thereof and consequently the length of the reciprocating stroke of the grinding wheel.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification considered in conjunction with the accompanying drawings 25 and it is to be understood that any modifications may be made in the specific structural details hereinafter shown within the scope of the appended claims without departing from or exceeding the spirit of the invention. r

In the drawings:

Figure 1 is a fragmentary perspective view a grinding wheel and the housing enclosing the spindle to which is secured a device of this invention.

Figure 2 is a sectional View taken on line of Figure 1.

Figure 3 is a sectional view on line 3--3 of Figure 2.

Figure 4 is a sectional View on line 4--4 of Figure 3.

Figure 5 is a view taken on line 5-5 of Figure 3.

Figure 6 is a sectional view taken on line 6-6 of Figure 4. Figure 7 is a fragmentary sectional View taken on line 7--'7 of Figure 1.

Figure 8 is a fragmentary elevational View as seen from line 8-8 of Figure '7. I

Throughout the several views of the drawings similar reference characters are employed to denote the same or similar parts.

Heretofore reciprocating attachments for effecting the reciprocation, through a limited scope of grinding wheels and their spindles have been employed for breaking up grinding lines and the like onwork pieces and to pro- Vide the desired finish thereon. These mechanisms, however, were generally fixed to provide a certain definite length of stroke without in anywise providing for adjustment thereof. This invention contemplates the provision of a mechanism that at the will of the operator may be adjusted to vary the length of the stroke from zero or no reciprocation to the maximum thereof.

As shown in the drawings there is disclosed one possible embodiment of the invention in which the numeral 10 indicates the base or supporting frame having secured thereto the housing 11 which encloses the grinding Wheel 12. Extending from the housing 11 is the bearing or bearings 13 for the grinding wheel spindle 14. The spindle 14 is so mounted in its bearings as to have no side or lateral play but has a clearance sufficient to permit the axial sliding or reciprocation of the spindle therethrough. As shown in Figure 3 the spindle 14 terminates in a reduced cylindrical portion 15 adjacent a further reduced threaded portion 16. The threaded portion 16 receives one end of a shaft 17 constituting an extension of the spindle which is journaled in anti-friction thrust bearing 18 contained within a sleeve 19. The sleeve 19 is in turn slidably mounted on a bearing 20 formed in the barrel portion 21 of the reciprocating mechanism housing 21a. A nut 22 is threaded into the open end of the sleeve 19 and locks the thrust bearing 18 within the said sleeve. Surrounding the shaft 17 at its outer end are a pair of spacing collars 23 and 24 which abut the adjacent sides of a washer 25 forming on opposite'faces a race for the anti-friction bearings or balls of the thrust bearing 18. The said collars 23 and 24 are locked to the shaft 17 with the washer 25 between them by a lock nut 26 threaded to the end of shaft 17.

Surrounding the shaft 1'7 and terminal portion .15 of the spindle 14 is a tubular worm shaft 27 having formed at one end a flange 28 abutting shoulder 29 of the spindle to which it is secured by fillister headed screws or the like 30 and having formed at its other end a worm 31. The shaft 27, therefore, derives its motion from the spindle 14 and has its worm 31 meshing with a Worm wheel 32 secured to a stud shaft 33. The shaft 33 is journaled on one end in a bearing 34 formed integrally with the housing 21a and on the other end in a removable plug or cap member 35. Extending beyond the bearing 34 the shaft 33 has an eccentric driving pin 36 received in a bore 3'7 formed in slide block 38. The block 38 isreceived between the arms 39 from any convenient or usual source, not shown,

is transmitted through the worm and Worm wheel to the stud shaft 33 for actuating the eccentric pin 38 and rocking the lever 41 about the fulcrum pin 45.

The oscillations of the lever 41 are converted into reciprocations of the spindle 14 through an arm 46 which extends from the sleeve 19 and has a pivotal connection at 47 with the said lever 41 substantially centrally of its length. The pivot 47 is mounted in a bushing or the like 48 carried by the said lever 41. The oscillations of the lever 41 may be varied to correspondingly vary reciprocations of the spindle 14 by shifting the fulcrum point 44 toward the power or driving eccentric pin 38 thereby changing the effective length of lever 41 and the throw thereof. To this end the fulcrum 44 is mounted in a nut 49 threadedly received by an adjusting screw 50 rotatably but non-translatably journaled in a bearing 51 extending upwardly from a cap or supplemental housing 52. The nut 49, see Figure 3, is provided with laterally extending arms 53 and 54 riding on the upper surface 55 of a channel like guide way 56 in which the body portion of the nut 49 is received. The channel portion 56 is provided at opposite ends with straps 57 and 58 which limit the longitudinal travel of the nut 49 and constitute the opposite limits of reciprocation of the grinding wheel spindle and wheel, in one instance the zero point and in the other the maximum reciprocation. For rotating the screw 50 it is provided on its end exterior to the supplemental housing 52 with a hand wheel 59.

As shown in Figure 3, the fulcrum 45 and pivot pin 47 are directly beneath one another so that oscillation of the lever 41 takes place about the aligned axial centers of the said fulcrum and pivot pin so that no movement is imparted to the sleeve 46 or spindle 14. At this time the nut 49 would be abutting the strap 58 so that the said strap will determine the zero or non-reciprocating point of the mechanism. In Figure 4, the fulcrum 44 and pivot pin 47 are shown in their other extreme position with the nut 49 abutting the strap 5'7 and in this position the maximum reciprocations will be imparted to the grinding wheel spindle 14 and grinding wheel 12.

The reciprocating mechanism is adapted to be actuated partly immersed in oil which is introduced into the housing 21a through a filling port formed in the cap bearing 35 and normally closed by a plug 60. The oil being drained from the chamber 61 through a port 62. In order that the operator may be advised of the amount of oil or lubricant within the housing there has been provided a sight gauge 63 secured to the end of barrel portion 21.

To determine and advise the operator the amount of reciprocation being supplied to sleeve 19 and spindle 14 an indicator arm 64 is utilized. As shown in Figure 7 the arm 64 is pivoted at 65 to the barrel portion 21 of housing 21a and the said arm has formed at one end thereof a pointer 66 cooperating with a dial or gauge 67 formed integral with the said barrel portion 21. The other end of arm 64 depends below the pivot 65 having a vertical slot 68 formed therein receiving one end of a pin 69 threaded at '70 into the sleeve 19. The pin 69 extends from the sleeve 19 through an elongated slot or perforation 71 for movement with the said sleeve 19.

From the foregoing it will be observed that the back and forth reciprocations of sleeve 19 will, through the pin 69 and depending portion of the arm 64, rock said arm about the pivot 65 causing the pointer portion 66 to indicate on the dial 6'? the length of stroke being imparted thereto.

The foregoing description fully discloses one possible modification of a readily adjustable rcciprocating mechanism for effecting the reciprocations of a grinding wheel spindle and grinding wheel of which many possible modifications could be made. The compactness and simplicity of the structure should be readily apparent to those conversant with this art.

What is claimed is:

1. In a spindle reciprocating mechanism for precision grinding machines the combination of a rotating spindle, bearings for the spindle, a sliding sleeve connected to the spindle, a bearing for the sleeve, a pivotally mounted lever having a pivotal connection with the sleeve, means driven by the spindle for oscillating the lever about its pivot and reciprocating the sleeve and spindle through the bearings, and means for adjusting the lever pivot relative to the lever from a point remote from the axis of the pivotal connection of the lever and sleeve to a point having the axes of the lever pivot and pivotal connection of the lever and sleeve coincidental.

2. In a reciprocating attachment for grinding wheels the combination of a rotating grinding wheel, a spindle for the grinding wheel, and means for axially reciprocating the spindle and grinding wheel comprising a housing, a sleeve slidably carried therein and operatively coupled with the spindle, a pivotally mounted lever within the housing, means driven by the spindle for oscillating the lever about its pivot, an adjusting screw rotatably but non-trans latably carried by the housing, a nut threadedly carried by the screw and bearing the lever pivot, and means exterior of the housing for adjusting the screw and changing the relationship of the pivot and lever to vary the oscil- .7 lations of the lever and length of stroke of the reciprocations of the spindle and grinding wheel.

3. In a reciprocating attachment for grinding wheels the combination with a rotating grinding wheel, a spindle therefor, of means for reciprocating the spindle and wheel comprising a pivotally mounted lever having one end thereof bifurcated and the other end channeled, a slide block in the forked end, a second slide. block in the channeled end, an eccentric driving pin received in the first slide block, a pivot pin in the second slide block about which the lever is oscillated by the eccentric driving pin, means connecting the lever with the spindle for changing said oscillations of the lever into reciprocations of the spindle, and means for adjusting the second slide block and pivot toward and from the eccentric driving pin to vary the throw of the lever and length of reciprocating stroke.

4. In a reciprocating attachment for grinding 150 wheels the combination with a rotating grinding wheel, a spindle therefor, of means for reciprocating the spindle and wheel comprising a pivotally mounted lever having one end thereof bifurcated and the other end channeled, a slide block in the forked end, a second slide block in the channeled end, an eccentric driving pin received in the first slide block, a pivot pin in the second slide block about which the lever is oscillated by the eccentric driving pin, means connecting the lever with the spindle for changing said oscillations of the lever into reciprocations of the spindle, means for adjusting the second slide block and pivot toward and from the eccentric driving pin to vary the throw of the lever and length of reciprocating stroke, said means including an adjusting screw, and a nut having threaded engagement therewith and supporting the pivot for movement along the screw.

5. In a reciprocating attachment for grinding wheels the combination with a rotating grinding wheel, a spindle therefor, of means for reciprocating the spindle and wheel comprising a pivotally mounted lever having one end thereof bifurcated and the other end channeled, a slide block in the forked end, a second slide block in the channeled end, an eccentric driving pin received in the first slide block, a pivot pin in the second slide block about which the lever is oscillated by the eccentric driving pin, means connecting the lever with the spindle for changing said oscillations of the lever into reiprocations of the spindle, means for adjusting the second slide block and pivot toward and from the eccentric driving pin to vary the throw of the lever and length of reciprocating stroke, said means including an adjusting screw, and a nut having threaded engagement therewith and supporting the pivot for movement along the screw, a housing enclosing the reciprocating means and having hearings in, which the screw is rotatably journaled, and. manual means exteriorly of the housing secured to the screw for rotatably actuating same.

6. In a device of the class described the combination of a rotating spindle, a housing therefor, a worm on the spindle extending beyond the housing, a supplementary housing enclosing the worm, an eccentric within the supplementary housing and driven by the worm, an oscillatable lever within the housing operatively connected with the eccentric, adjustable pivot means for the lever about which the oscillations thereof take place, means connecting the lever with the spindle for effecting reciprocations of the spindle, and means accessible exteriorly of the housing for adjusting the pivot toward and from the spindle connection for varying length of reciprocations of the spindle, said means comprising a screw journaled in the supplemental housing, a nut threaded on the screw and supporting the lever pivot, and manual means for actuating the screw.

7. In a device of the class described the combination of a rotating spindle, a housing therefor, a worm on the spindle extending beyond the housing, a supplementary housing enclosing 100 the worm, an eccentric within the supplementary housing and driven by the worm, an oscillatable lever within the housing operatively connected with the eccentric, adjustable pivot means for the lever about which the oscillations 105 thereof take place, means connecting the lever with the spindle for efiecting reciprocations of the spindle, means accessible exteriorly of the housing for adjusting the pivot toward and from the spindle connection for varying length 110 of reciprocations of the spindle, said means comprising a screw journaled in the supplemental housing, a nut threaded on the screw and supporting the lever pivot, manual means for actuating the screw, and means visionable 11,5 exteriorly of the housing movable at the same rate and through the same range as the spindle for indicating the length of reciprocations of the spindle. 

